Such a system is known, for example, from patent application laid open DE 10 2009 045 403 A1. The device there serves to separate gas and liquid or generally to separate a dispersed phase from a continuous phase and for this purpose it has an intake channel and a discharge channel for the gas and liquid mixture. Between the two channels is arranged a membrane in the form of several capillary channels, which join the intake channel to the discharge channel. The separation of the two phases occurs by a controlling of the pressure difference between the first and the second channel, taking into account the capillary forces in the capillary channels, wherein the wetting behavior ensures that the gas by virtue of the surface tension is held back and collected either before or in the capillary channels until all of the capillary channels are blocked by the increasing gas bubble. After this there occurs a pressure increase with which the gas bubble ultimately overcomes the surface tension and is emptied through the capillary channels. This device can be used on the one hand to determine the position of a gas accumulation, to determine the position of a liquid drop, or to separate the gas and liquid mixture. Depending on the application, it may be a drawback in this or similar systems that the membranes due to the wetting behavior hinder the transport of the liquid upon entering or leaving the membrane so much that high pressures or pressure differences are needed under such alternating drying, wetting, and drying. In many applications, the required pressure differences cannot be produced in a microfluidic system or the membranes cannot withstand them mechanically or a breakthrough of the liquid through the membrane results in an uncontrolled liquid transport. Furthermore, it can happen that the capillary channels in event of a breakthrough are not necessarily completely emptied, so that unwanted liquid residues remain on and in the membrane.